Rinnai V53e Propane Outdoor Tankless Water Heater – You’ll stop planning your mornings and evenings around your hot water heater and set your own schedule, thanks to the V53e. Some additional details about the Rinnai V53e Propane External Tankless Water Heater include: Ideal for one- to two-bathroom homes, the V53e delivers up to 5.3 gallons of hot water per minute (GPM) at a 35 degree temperature rise, while saving energy and money. Easy to install on the exterior of your home, the V53e frees up interior space and saves on installation and construction costs. The Rinnai V53e-LP exterior-mounted V Series, 5.3 GPM, Propane, .82 Energy Factor Tankless Hot Water Heater units are easy to install on the exterior of your home, the V53e frees up interior space and saves on installation and construction costs